. The power of movement in plants . Plants; Botany. Ohap. XI. TKANSMITTED EFFECTS : VICIA. 527 Fig. 195. former trial; and after their tips (1-5 mm. in length) had been amputated, they were placed vertically in damp peat. Of these, three were not in the least affected and continued for days to grow straight downwards. Tour showed after 8 h. 30 m. a mere trace of curvature in the direction in which they had been acted on by geotropism; and in this respect they differed much from those which had been exposed for 1 h. 37 m., for many of the latter were plainly curved in 6 h. The curvature of one
. The power of movement in plants . Plants; Botany. Ohap. XI. TKANSMITTED EFFECTS : VICIA. 527 Fig. 195. former trial; and after their tips (1-5 mm. in length) had been amputated, they were placed vertically in damp peat. Of these, three were not in the least affected and continued for days to grow straight downwards. Tour showed after 8 h. 30 m. a mere trace of curvature in the direction in which they had been acted on by geotropism; and in this respect they differed much from those which had been exposed for 1 h. 37 m., for many of the latter were plainly curved in 6 h. The curvature of one of these four radicles almost disappeared .after 24 h. In the second, the cur- vature increased during two days and then decreased. The third radicle became permanently bent, so that its terminal part made an angle of about 45° with its original vertical direction. The fourth radicle became horizontal. These two latter radicles continued during two more days to grow in the peat in the same directions, that is, at an angle of 45° be- Viciafaba: rndicle, rectangularly. neath the horizon and horizon- tally. By the fourth morning new tips had been re-formed, and now geotropism was able to act on them again, and they became bent perpendicularly downwards, exactly as in the case of the five radicles described in the last paragraph and as is shown in bent at A, after the imputation of the tip, due to the previous influence of geotropism. L, side of bean which lay on the peat, whilst geotropism acted on the ralicle. A, point of chief cur- vature of the radicle, whilst standing vertically downwards. B, point of chief curvature after the regeneration of the tip, when geotropism again acted. C, re- generated tip. the figure (Pig. 195) here given. Lastly, five other radicles were similarly treated, but were ex- posed to geotropism during only 45 m. After 8 h. 30 m. only one was doubtfully affected; after 24 h. two were just per- ceptibly curved towards the side which had been acted on by
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